Compare Central Bank Rates

On this page, we’ll dive into the official rates compare endpoint you can use to see one currency pair, for example EUR to USD, as every central bank published it, side by side.

Central banks fix their rates at different times of day and from different data, so the ECB, the Federal Reserve and the Bank of England rarely agree on EUR to USD to the last digit. This endpoint puts their figures next to each other and tells you how far apart they are, for example to pick the source your rules prescribe or to check a rate you were given. The values come from the same publications as /v3/official.

curl -G https://api.currencyapi.com/v3/official/compare \
    -d base_currency=EUR \
    -d currency=USD \
    -d date=2026-09-26 \
    -H "apikey: YOUR-API-KEY"

{
    "meta": {
        "base_currency": "EUR",
        "currency": "USD",
        "requested_date": "2026-09-26",
        "sources": 3,
        "high": 1.140645161,
        "low": 1.139999977,
        "spread_pct": 0.0566
    },
    "data": [
        {
            "source": "ecb",
            "source_name": "European Central Bank",
            "country": "EU",
            "date": "2026-09-25",
            "value": 1.1403,
            "cross_rates": false,
            "reference": null
        },
        {
            "source": "boe",
            "source_name": "Bank of England",
            "country": "GB",
            "date": "2026-09-25",
            "value": 1.140645161,
            "cross_rates": true,
            "reference": null
        },
        {
            "source": "fed",
            "source_name": "Federal Reserve",
            "country": "US",
            "date": "2026-09-25",
            "value": 1.139999977,
            "cross_rates": false,
            "reference": null
        }
    ]
}

Direct and cross rates

• Direct. A bank that publishes against one of the two currencies gives the rate directly: the ECB publishes USD per 1 EUR, and the Federal Reserve publishes its EUR rate against USD. cross_rates is false.
• Crossed. A bank that publishes both currencies against its own gives a cross rate computed from those two official rates: the Bank of England publishes USD and EUR against GBP, so its EUR to USD is its USD rate divided by its EUR rate. cross_rates is true.
• Left out. Banks that do not publish both currencies are not listed. When no bank (of sources) does, the response is a 404 with error.code no_rates_published.

Choosing the banks

sources=ecb,fed compares only those banks; the order of the list does not matter. An unknown code returns a 422. /v3/official/sources?currency=USD lists every bank that publishes a currency.

CSV and Excel

With format=csv you get one row per bank, format=xlsx gives the same table as an Excel workbook named official-compare.xlsx:

curl -G https://api.currencyapi.com/v3/official/compare \
    -d base_currency=EUR \
    -d currency=USD \
    -d date=2026-09-26 \
    -d sources=ecb,boe,fed \
    -d format=csv \
    -H "apikey: YOUR-API-KEY"

source,source_name,country,date,base_currency,currency,value,cross_rates,reference
ecb,European Central Bank,EU,2026-09-25,EUR,USD,1.1403,false,
boe,Bank of England,GB,2026-09-25,EUR,USD,1.140645161,true,
fed,Federal Reserve,US,2026-09-25,EUR,USD,1.139999977,false,

Errors

{
    "message": "No central bank published both EUR and XAU on or shortly before 2026-09-26.",
    "error": {
        "code": "no_rates_published",
        "message": "No central bank published both EUR and XAU on or shortly before 2026-09-26."
    },
    "actions": {
        "sources": "https://api.currencyapi.com/v3/official/sources",
        "docs": "https://currencyapi.com/docs/openapi.yaml"
    },
    "info": "For more information, see documentation: https://currencyapi.com/docs/official"
}

See Request Status Codes for the errors every endpoint shares.